An Israeli think tank said in a study it released on Thursday that Hamas' military buildup is at its peak, despite the international blockade on the Gaza Strip.

In an estimate of the current strength of the militant group's forces, the think tank said Hamas had organized 20,000 armed forces and acquired long-range rockets and advanced anti-tank weapons.

The Intelligence and Terrorism Information Center also said that Israel's 2005 pullout from Gaza enabled the militant Palestinian group to boost its power in the coastal strip, over which it gained control in a violent takeover in June 2006.

"The Israeli disengagement from the Gaza Strip in August 2005 created a new situation which accelerated the establishment of an area fully controlled by Hamas. It was quick to use its increased military power to make political capital in internal Palestinian affairs," the study states.

Iran and Syria supply Hamas with weapons, technical knowhow and training, the study also stated.

Futhermore, the study said the Islamic group has smuggled 80 tons of explosives into the Gaza Strip since it seized the territory last year.

Referring to Hezbollah, the study described the Lebanese guerilla group's "success in providing an asymmetric response to the Israel Defense Forces' might" during the Second Lebanon War as having made it a role model for Hamas.

The center has close links to Israel's defense establishment and based its report on data supplied in part by the Shin Bet security service.